I knew that the “two-thirds” sensor, common in compact SLRs, has a magnifying impact on an image compared to the “full frame” sensor found in the mid-size and pro SLRs, but I’d never seen the effect of this 1.6x magnification with my own eyes until today.

Test 1 – Wide angle

The “two-thirds” (22.3mm) APS-C sensor in my 650D has the effect of magnifying an image by 1.6x compared to the “full frame” (36mm) sensor of the 5D, meaning that at the same focal length my camera can’t fit as much into the image as it’s big brother. Both these shots were taken at each lens’s widest angle (17mm vs 18mm respectively).

Notice, for example, how the bench and flower pots in the foreground are complete in the first image, but cropped in the second one: